Abstract

The biodegradation potential of Fusarium spp was investigated on soil experimentally polluted with crude oil. The fungal load dynamics of Fusarium spp. and the physicochemical parameters of the polluted soil were determined using standard microbiological and analytical (Spectrophotometer, model APEL PD-303UV) methods. The parameters were determined at weekly intervals and at varying levels of crude oil concentration (10%, 20%, 30% and 40%) for a period of six weeks. There was a progressive increase in the fungal load dynamics (3.0×104Â±0.05cfu/g-1.41×105Â±0.06cfu/g; 2.9×104Â±0.02cfu/g- 1.32×105Â±0.02cfu/g; 3.2×104Â±0.04cfu/g-1.41×105Â±0.05cfu/g and 2.4×104Â±0.01cfu/g-1.30×105Â±0.02cfu/g) from week one to week six at 10%, 20%, 30% and 40% crude oil concentrations respectively. The highest fungal load (1.41×105Â±0.06cfu/g ) was recordedÂ on 10% crude oil concentration at week six while the lowest fungal load (2.4×104Â±0.01cfu/g) was recorded on 40% crude oil concentration at week one. The result of the total petroleum hydrocarbon (TPH) showed a progressive decrease (1410.6Â±0.215mg/kg-363.03Â±0.215mg/kg;1446.0Â±0.215mg/kg-422.77Â±0.215mg/kg;1589.6Â±0.215mg/kg-853.47Â±0.215mg/kg and 1948.4Â±0.215mg/kg-858.28Â±0.215mg/kg) from week one to week six at 10%, 20%, 30% and 40% crude oil concentrations respectively. Other physicochemical parameters such as pH (5.4Â±0.005-6.3Â±0.005), percentage nitrogen (0.14Â±0.029%-0.364Â±0.029%) and electrical conductivity (12.25Â±0.015Âµs -22.2Â±0.015Âµs) showed progressive increase as observed on the 10% crude oil concentration from week one to week six respectively. The result indicates the potential of Fusarium spp. in the degradation of crude oil as evidenced in the progressive reduction in the total petroleum hydrocarbon. The use of Fusarium spp. in the bioremediation of crude oil polluted sites is recommendable.